At the end of Manchester City's 1-1 draw with Borussia Dortmund Joe Hart was asked about an astonishing performance in which he had made six or seven superb saves to rescue his side. He shrugged and replied: "I hope it was worth it." Wednesday night will go some way to showing whether it was. Not just because of what happens between City and Ajax but because of what happens in Germany, where Real Madrid face Dortmund in the first of two successive games between the clubs.

It may appear to be good news for City that Madrid have won only once in Germany, over a decade ago. Madrid are also without all three of their left-backs, Marcelo, Fábio Coentrão and Alvaro Arbeloa, who all picked up injuries during the international break. At the weekend José Mourinho used Michael Essien at left-back and looks likely to repeat that here, although he suggested that the demands of this game may be different from those of Celta de Vigo and said: "There are other players that, although they are not left-backs professionally or in their spare time, can do it."

"This is a difficult game but not because we are missing players: we have the players to play this game," Mourinho said. "It is difficult because our opponents are a difficult team and this is a difficult group. It is not the kind of group where you can be qualified after three games or you can break the record and get 18 points from 18 like we did last season. We want to get through: we won't want to be the big team in the Europa League."

Sami Khedira, one of two Germany internationals in the Madrid side along with Mesut Ozil, added: "Dortmund are a great team but so is Manchester City. They made it very difficult for us in the first game, and we only won in the last minute. The three teams are great teams, so we can't say that we should only focus on Borussia.

"Dortmund are a compact team. They play at great pace for 90 minutes and are very disciplined. They have a lot of quality, especially in attack. And I know the stadium from my time at Stuttgart: it has a special atmosphere. If we win, it will be a big step towards qualification," he said.

City, too, wish to avoid Europa League football and, for them to do so, it could prove to be in their interests for Madrid to win the group now, defeating Dortmund twice to keep qualification in second place within City's grasp. But this is a hurdle that Madrid have struggled to overcome and Dortmund's performance in Manchester was watched with admiration.

"I seem to remember that the last time we won in Germany was against Leverkusen 12 years ago. We beat them 2-3 and it was difficult," the Madrid captain, Iker Casillas, said. "We hope to get the three points that I think would almost qualify us for the next round and give peace of mind of being in the last 16 but we know it will not be easy. It is always hard to play in Germany."

Madrid have made 23 trips to Germany and won once, against Bayer Leverkusen. Six draws and 16 defeats tell the tale. Cristiano Ronaldo has not scored in Germany either but he has 55 goals in 2012, 11 of them in the Champions League, and Madrid are the competition's top scorers. "There's no psychological problem," said Mourinho. "If Madrid have not won in Germany often it is because it is hard to do so."

Much like last year City have found themselves in the competition's hardest group. The draw at the Etihad was vital: it leaves them trailing Dortmund by four points rather than six. They are five points behind Real Madrid. In a group in which Ajax have already been beaten twice and appear the clearest source of points, City's aim must be to emerge from these next two matches with seven points in all. But even that may not be enough. Madrid and Dortmund will have their say.